2-Carb-19

Continued from 2-Carb-18

Contents

• 2-Carb-19. Alditols
  • 19.1. Naming
  • 19.2. meso Forms

2-Carb-19.1. Naming

Alditols are named by changing the suffix '-ose' in the name of the corresponding aldose into '-itol'.

If the same alditol can be derived from either of two different aldoses, or from an aldose or a ketose, preference is ruled by 2-Carb-2.1 or 2-Carb-2.2.2 as appropriate.

Examples:

D-glycero-L-galacto-Heptitol
not L-glycero-D-manno-heptitol

D-erythro-L-galacto-Octitol
not D-threo-L-gulo-octitol

D-Arabinitol (Ara-ol) not D-lyxitol

D-Glucitol (Glc-ol) not L-gulitol
(the trivial name sorbitol is not recommended)

The trivial names fucitol and rhamnitol are allowed for the alditols corresponding to the 6-deoxy sugars fucose and rhamnose.

L-Fucitol (L-Fuc-ol) or 1-deoxy-D-galactitol
not 6-deoxy-L-galactitol (cf. 2-Carb-2.2.3.1)

L-Rhamnitol (L-Rha-ol) or 1-deoxy-L-mannitol

2-Carb-19.2. meso Forms

Alditols that are symmetric and therefore optically inactive - the meso forms - can be designated by the prefix meso-.

Examples:

The prefix D or L must be given when a derivative of a meso form has become asymmetric by substitution. It is also necessary to define the configurational prefixes as D or L in the case where there are more than four contiguous asymmetric carbon atoms.

Examples:

meso-D-glycero-L-ido-Heptitol
not L-glycero-D-ido-heptitol; cf. 2-Carb-2.2.3

5-O-Methyl-D-galactitol
not 2-O-methyl-L-galactitol

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